(1) Field of the Invention
The present invention relates to fire protection. More specifically, this invention is directed to devices and systems having an indefinite shelf life which, when subjected to an elevated temperature, will absorb heat and release a non-toxic, non-flammable gas. Accordingly, the general objects of the present invention are to provide novel and improved techniques and articles of such character and methods for the production of such articles.
(2) Description of the Prior Art
Flame retarding and/or extinguishing systems including chemicals, such as inorganic carbonates, which undergo an endothermic reaction to release non-toxic and non-flammable gases when subjected to elevated temperatures are known in the art. Exemplary of the prior art are the disclosures of U.S. Pat. Nos. 100,632, 639,674, 967,246, 1,813,367, 2,388,014, 3,238,129, 3,364,097, 3,714,047, 3,782,476, 3,826,764 and 4,184,311.
The prior art, as represented by the above-identified patents, has possessed one or more serious deficiencies which have limited the utility thereof. Thus, by way of example, the prior systems have had poor "shelf" life whereby their effectiveness in affording protection from and/or in the extinguishing of fire would degrade with time. At least some of the prior art systems, to remain effective, required periodic recharging and thus could not be counted upon to always be ready for use. Also, the prior techniques and systems have generally been characterized by high production cost. A further common deficiency of the prior art resides in the fact that products embodying the same have necessarily had very poor volumetric efficiency, for example have necessarily been rigid, and thus have been difficult and expensive to store. This lack of volumetric efficiency has also led to a lack of utilization in many situations.